by Louise-Océane Delion, marine biologist and scientific content creator for Koraï
Introduction
What do we really lose when we lose nature? Or, to put in another way, what does nature offer us without us even realizing it?
As ecosystems are being degraded all over the world, we are starting to realize the true value of biodiversity on this planet, not just for the goods it provides us with but for all the services that sustain us and all life on Earth.
The term « ecosystem services » has been coined to assess how much natural ecosystems supporting human beings are worth. It helps us to envision ecosystems in a holistic way and to understand the consequences of destroying them the way we do.
Dive with us as we explore the concept of ecosystem services, what marine ecosystems provide us with, and how we can help to restore ecosystems to restore their services.
Understanding the concept of ecosystem services
In the 80s, a new field known as « ecological economics » emerged with the aim of evaluating the services provided by nature in economic terms. In 1997, two key publications - a book and an article in the scientific journal Nature - laid the foundation for what we know today as « ecosystem services ». They synthesized all the information into a global quantitative assessment of the value of ecosystem services: at that time, the entire biosphere was valued at US$33,000 billion per year1.
Ecosystem services are defined as the ecological characteristics, functions or processes that contribute directly or indirectly to human well-being. They are the benefits people derive from functioning and healthy ecosystems.
They are divided into different categories such as :
Provisioning services (food, water, timber…)
Regulating services (flood control, storm protection, water regulation, pollination, climate regulation…)
Cultural services (aesthetic, sense of place, scientific, educational and indigenous knowledge…)
Supporting services (basic processes such as primary production, nutrient cycling, and photosynthesis…) that support the three other categories.
In conventional economics, ecosystems are usually valued based on their products once they are harvested and sold in markets, and not for all the other services they provide before they are exploited, from which humans also benefit, consciously and unconsciously.
The objective of valuing ecosystem services in a more holistic way is to demonstrate that the whole system matters and that we need to give them way more credit than what conventional economics do.
Estimating the value of ecosystem services in monetary units is also a way of speaking the « human language » and comparing them to other services we know and care about. It is not about « trying to sell nature » but rather to emphasise the importance of natural ecosystems and the urgent need to consider them better in the way we do business and govern.
What marine ecosystems offer us
As land animals, it is perhaps a little harder to envision how marine and coastal ecosystems contribute to human well-being and support our global life system.
Marine ecosystem services go far beyond the fish they provide us as food or the joy they give us when we go swimming :
They provide us with raw materials, food, water, biofuels… They protect the coast from floods, erosion and storms. They capture and store carbon, regulate the chemical composition of the atmosphere and the ocean, the Earth’s temperature and humidity, and control pollution. They serve as breeding and nursery habitats for most marine species. They offer aesthetic experiences with playgrounds for tourism and recreation. They have a religious and spiritual aspect for certain populations and individuals. They contribute to our mental and physical health and fill us with joy2. And the list goes on…
If we look at the example of mangrove forests, seagrass beds or coral reefs, it is clear how humans directly depend on them:
These three habitats interact to contribute to the life cycle of marine life, serving as breeding and nursery areas, and supporting fisheries and tourism activities.
They protect coastal areas by absorbing wave energies coming from the open ocean, reducing the economic damage that storms and erosions could inflict on properties and communities.
They capture and store an incredible amount of carbon, helping us to reduce the impacts of climate change.
In Africa, the annual value of ecosystem services provided by mangroves, corals and seagrass has been estimated at 814 billion USD. Most of these services are provided by coral reefs with a value reaching 352,250 USD/ha/year, or is about 588 billion USD/year in the whole of Africa!3
Losing nature and losing value
The provision of ecosystem services depends on the state of the ecosystem: only healthy ecosystems can provide highly valuable services.
With the increasing pressure put on the world’s ecosystems through human activities, and ecosystems being degraded and disappearing globally, the value of ecosystem services keep declining too.
The degradation of coastal ecosystems due to urban development, overfishing, pollution and climate change has been altering their capacity to provide essential ecosystem services, and ultimately affecting us.
For example, the global coverage of living coral has declined by half since the 1950s. As a consequence, the capacity of coral reefs to provide ecosystem services has also halved over the same period of time, particularly in terms of the food supply they support. The loss of many fish stocks will impact millions of people in coastal communities who rely on coral reefs for food, culture and livelihoods.4
Restoring ecosystems to restore their services
There is clearly an urgent need to effectively protect and restore ecosystems in order to ensure their long-term provision of goods and services, and to find a sustainable way of interacting with them (economically, socially, and culturally…).
Ecological restoration (the process of assisting the recovery of an ecosystem) has been shown to increase biodiversity levels and subsequently the provision of ecosystem services. Some services may be regained relatively quickly following restoration efforts while others might take longer, but overall, there is always improvement and an opportunity to put back nature on track.5
Investing money in ecosystem restoration is a wise investment, not only for biodiversity itself but also for our survival. Investing in ecosystem restoration is a way to sustain (or revive) the provision of ecosystem services on which we depend!
Marine ecosystem restoration projects have already produced very good results where essential ecosystem services are reaching previous historical levels and will keep contributing to human well-being.6
As mentioned before, the ecosystem services provided by coastal ecosystems in Africa are highly valuable. Unfortunately, they are also being impacted by anthropogenic activities. This is why at Koraï, we are restoring marine ecosystems in Africa, starting with coral reefs in Madagascar. Our aim to bring back life in the ocean and restore the ecosystem services that support coastal communities and all humans on Earth. Will you join us ?
References for further reading
1 Costanza, R. et al., (1997). The value of the world's ecosystem services and natural capital. Nature, 387(6630), 253-260.
2 Barbier, E. B. (2017). Marine ecosystem services. Current Biology, 27(11), R507-R510.
3 Trégarot, E. et al., (2020). Valuation of coastal ecosystem services in the Large Marine Ecosystems of Africa. Environmental Development, 36, 100584.
4 Eddy, T. et al., (2021). Global decline in capacity of coral reefs to provide ecosystem services. One Earth, 4(9), 1278-1285.
5 Benayas, J. et al., (2009). Enhancement of biodiversity and ecosystem services by ecological restoration: a meta-analysis. Science, 325(5944), 1121-1124.
6 Orth, R. et al., (2020). Restoration of seagrass habitat leads to rapid recovery of coastal ecosystem services. Science Advances, 6(41). & Hein, M. et al., (2021). Perspectives on the use of coral reef restoration as a strategy to support and improve reef ecosystem services. Frontiers in Marine Science, 8, 299.